SU1729381A1 - Device for grading of curled green tea leaves - Google Patents

Abstract

The invention relates to food pro-. thinking and can be used in tea factories of primary processing. The purpose of the invention is to improve the quality of sorting a twisted sheet of various fractional composition according to tenderness and process intensification. The device comprises a frame 1, a vibrating duct 10 with a screen bottom 11, a hopper 29 with a loosening-knife device 31-33, a conveyor 34 for carrying out the fines. The fastening mechanism of the loading area of the sieve on frame 1 is rigidly attached to the duct 10 by a pair of eyelets with radial bearings, mounted on the knee of the crankshaft of the vibrodrive. The mechanism for fastening the discharge section of the sieve on the frame is formed by two suspensions 12 with the possibility of changing their length. The hinges 13 connecting the hangers 12 with the frame 1 are mounted with the possibility of changing the location of the hinges in height, and the hinges 14 connecting the hangers 12 with the discharge section of the sieve with the possibility of changing the location of these hinges along the duct 10. 4 Il. (Ls

Description

h yu

CJ 00

FIG. one

The invention relates to the food industry, in particular, to the technique of sorting twisted green tea leaves under the conditions of vibration of a sorting screen, and can be used in tea factories of primary processing.

The purpose of the invention is to improve the quality of sorting a twisted sheet of various fractional composition by tenderness and intensification of the process.

To achieve this goal, a device for twisting twisted green tea leaves containing a frame, a loading hopper, a sieve with loading and unloading areas and a drive for communicating the sway of the oscillating movement, the drive of the sieve includes a crankshaft, the knee of which by means of radial bearings and eyelets connected to the loading area of the sieve, while the unloading area of the sieve is mounted on the frame with adjustable length suspensions with hinges at the ends, and the hinges connecting The suspensions with the frame are mounted with the possibility of changing the position in height, and the hinges connecting the suspensions with the unloading section of the sieve with the possibility of changing the position along the latter.

In the proposed device for sorting the twisted tea leaf, the exit portion of the sieve bottom oscillates (rolls) in an arc with a convexity downwards, i.e. with radius facing up. In such conditions, the vibratory movement of the sieve, along with the movement of the twisted tea leaf along the sieve, promotes intensive screening of small twisted tea cups through the sieve hole, as during the zigzag movement of the twisted tea leaf along the sieve, at the moments of tea dropping on the tea sieve, the tea leaves move almost perpendicular to the screen surface. i.e. directed along the sieve holes. The device provides the opportunity to adjust the angle of inclination and the amplitude of oscillations of the sieve, which allows the sorting process to be carried out under optimal conditions depending on the conditions of twisting of the tea leaf and its fractional composition according to tenderness.

Fig. 1 shows a device for sorting a twisted green tea leaf, a general view; figure 2 - section aa in figure 1; on fig.Z - section bb in fig, 1; in FIG. 4, node I in FIG. 3.

A device for sorting twisted green tea leaves contains

the support frame 1, which has vertical sections of the squares 2, connected to each other by means of the board 3. On the frame 1 there is installed a vibrator case 4 that includes a crankshaft 5 with counterweights 6 and 7. The crankshaft 5 is installed in bearings 8. The counterweight 7 also serves as a pulley for driving the shaft 5 in rotation from the electric motor through a belt drive (not shown). The crankshaft 5 is fitted with sockets 9 by means of radial bearings, which are rigidly attached to the loading end of the box 10. Box 10 has a rectangular screen bottom 11 of

5 of the extruded sheet material or interlaced steel or nylon mesh, and in the direction of the discharge end, is supported on the board 3 by means of a pair of suspensions 12 and fixing hinges 13 and 14.

0 Each suspension 12 contains upper and lower screw rods 15 and 16 and a long connecting nut 17c with oppositely directed helical surfaces 18 and 19. For example, if the upper portion

5, the nut 17 has a left approach of the screw surface 18, then the lower portion of the nut should have a right approach of the screw surface 19. The screw surface of the rod 15 is made in accordance with the screw

0 surface 18 of the nut 17. The screw surface of the stem 16 is made in accordance with the screw surface 19 of the nut. The hinge 13 comprises an axis 20 with a radial bearing 21 associated with the rod 15,

5 The axis 20 is rigidly connected to the bolt 22, which is fixed to the board 3 by means of two nuts 23 and 24. The lower hinge 14 comprises an axis 25 with a radial bearing 26 connected to the stem 16. The axis 25 by means of a nut 27

0 is rigidly fixed in the longitudinal opening 28 of the box 10. A hopper 29 is located above the vibrator body 4, in the lower part of which are shafts 30 and 31. There are disk knives 32 fixed on the shaft 30, and

5 shaft 31 - cutting plates 33. in the lower part of the device under the duct is a remote conveyor 34 with reversible drive (not shown).

In order to prevent unauthorized twisting of the connecting nut 17, each suspension 12 contains a lock nut 35. For mounting the axis 20 onto the bolt 22, a bracket 36 is used,

A device for sorting twisted green tea leaves works as follows.

Pre-box 10 and, therefore, the sieve bottom 11 is installed in the desired position by adjusting the location of the suspensions 12. It is possible to move the hinge 13 vertically with nuts 23 and 24. The hinge 14 can be advanced along the opening (hole) 28 and the sieve bottom 11 and set to the desired position by means of the axis 25 of the hinge 14 and the nut 27. The length of the suspension 12 is adjusted by turning the nut 17 in the desired direction, with the rods 15 and 16 approaching or moving away from each other. After the nut 17 is installed in the desired position, the lock nut 35 is clamped in order to prevent the nut 17 from turning during operation of the device.

Electric drives (not shown) of the crankshaft 5, shafts 30 and 31 and conveyor 34 are turned on and the metered supply of the twisted tea leaf is started in the bunker 29, in which the twisted leaf is exposed to rotating disc knives 32 and cutting plates 33. Tea leaves, between the the cutting edges of the plates and knives are crushed, loosened and fed to the screening sieve (screen bottom) 11 of the box 10. Due to the vibration of the box 10 from the crankshaft 5, the twisted tea leaf moves along the sieve, making an abrupt movement with a given frequency (240-300). Small tea leaves are sifted through the holes of the screen 11 and removed from the device by the conveyor 34. Large, non-twisted tea leaves reach the end of the box 10 and are unloaded from it (gathering).

The constructive solution of the device allows to change the nature of vibration of the system 11 from the loading to the discharge end. The knees of the shaft 5 and the axis of the socket 9 rotate around the axis of the bearings 8, and the hinges 14 oscillate (reciprocating) around the hinge 14 along an arc with a radius corresponding to the length of the suspension 12. The elements (points) of the sieve loading section oscillate (rotate) approximately on ellipsoid trajectories x, the difference between the large and small diameters of the ellipse decreases for points located near the crankshaft 5 and increases for points more separate from shaft 5. As it moves from the loading end of the sieve 11 to its From the loading end of the trajectory of movement of the elements (points), the sieves from an ellipsoidal shape are gradually transformed into an arcuate shape with a convexity facing down. This creates favorable conditions for the passage of small tea leaves along the sieve opening, especially in the central and discharge portions of the sieve. This is due to the fact that with the spasmodic movement of the twisted tea leaf in the central and unloading areas of the sieve at the moment of the falling of individual tea leaves, their movement is directed almost perpendicularly to the arcuate trajectory of the sieve elements (points), i.e. The tea bags are directed almost parallel to the axis of the sieve holes, which improves the conditions for the passage of small tea leaves through these holes and thus intensifies the process and improves the quality of sorting.

The design of the device reduces the vibration amplitude of the sieve vertically from the loading end of the sieve to the unloading one, which leads to a gradual decrease in the speed of movement of the twisted tea leaf on the sieve: the speed of the tea leaves coming to the sieve is maximum and the speed of the tea leaves coming off the sieves (descent) is minimal. By adjusting the angle of inclination and the amplitude of vibration of the sieve, it is possible to achieve such a thickness of the sheet layer in its individual sections, at which the screening capacity (sorting capacity) of each section of the sieve is used efficiently, which ultimately leads to an intensification of the process and improvement of the sorting quality.

It was established experimentally that under conditions of increased content of the coarsened and coarse fraction in the harvested tea raw materials (above 30%), the positive slope of the sieve is more effective (the discharge end of the sieve is located below the loading one). At the same time, the oscillation amplitude is reduced by means of fixing hinges. In this case, the speed of movement of the twisted tea leaf on the sieve surface increases with a decrease in the amplitude of the sieve vibrations and the screening (sorting) capacity of the device decreases, which ensures that the sifted fraction is obtained in a cleaner form without significant content of coarse and coarse crushed leaves and stems, which, in this case, are separated as much as possible together with the similar fraction, as a result, the qualitative composition of the small sifted fraction is improved.

Under conditions of low coarse and coarse fractions (less than 30%), the negative slope of the sieve is more effective (the discharge end of the sieve is located above the loading end), while using the fastening hinges it increases the amplitude of oscillations. In this case, the speed of movement of the twisted tea leaf on the sieve surface decreases while simultaneously increasing the amplitude of the sieve vibrations, which provides an increase in the screening (sorting) capacity of the device and the output of the small sifted fraction.

Thus, the proposed technical solution in comparison with the known one allows to intensify the process and improve the quality of sorting the twisted tea leaves of different fractional composition according to tenderness.

Claims (1)

Invention Formula A device for sorting a twisted green tea leaf, comprising a frame, a loading hopper, a sieve with loading and unloading sections and an actuator for communicating an oscillating movement situation, characterized by 0 five By the fact that, in order to improve the quality of sorting the twisted sheet of different fractional composition according to tenderness and process intensification, the sieve drive includes a crankshaft, whose knee is hinged to the loading section of the sieve by means of radial bearings and eyelets adjustable length suspensions with hinges at the ends, moreover, the hinges connecting the suspensions to the frame are mounted with the possibility of changing the position in height, and the hinges connecting the suspension and a discharge portion sieves, - with the possibility of varying the position along the latter.